1. Field
One embodiment of the invention relates to a motion-adaptive non-interlace conversion apparatus and conversion method. In particular, a cross-color & dot interference elimination circuit is effectively combined, and the image quality can be enhanced, the number of structural elements can be reduced and the driving load can be decreased.
2. Description of the Related Art
In a case where an interlace image signal is to be converted to a non-interlace image signal, a motion-adaptive non-interlace conversion circuit is used. Normally, when this kind of image signal processing circuit is constructed, consideration is given to the reduction in circuit scale and in number of memories used. Such motion-adaptive non-interlace conversion circuits are disclosed, for example, in Jpn. Pat. Appln. KOKAI Publication No. 11-150708, Jpn. Pat. Appln. KOKAI Publication No. 10-098694 and Jpn. Pat. Appln. KOKOKU Publication No. 08-032075.
In KOKAI No. 11-150708, three field memories for inter-field interpolation, motion detection and time/space filtering in a motion-adaptive scan-line interpolation circuit are integrated into a single system. This technique is intended to reduce the circuit scale.
In KOKAI No. 10-098694, in a motion-adaptive scan-line conversion process, interlace image signals are subjected to sub-sampling at a ratio of 2:1, and a signal of a preceding field with the reduced ½ sampling points is generated. A still-image mode interpolation scan-line signal is generated from neighboring upper and lower scan-line image signals of the preceding field with the reduced ½ sampling points and the current field. Thereby, the memory capacity is reduced.
In KOKOKU No. 08-032075, a motion detection circuit is shown. As regards signals indicative of image motion amounts, a representative value that represents a plurality of signals is calculated. This representative value is used in an image motion amount processing circuit.
In the meantime, in an image signal processing circuit, a cross-color & dot interference elimination circuit is used in order to enhance the image quality or to suppress degradation in image quality. In some cases, the cross-color & dot interference elimination circuit is disposed on the front stage of a motion-adaptive non-interlace conversion circuit.
The object of the present invention is to provide a motion-adaptive non-interlace conversion apparatus and conversion method, wherein the control of memories is easy and the circuit scale can be reduced.